The structure of Coppinger's radical and its orientation within a cluster of a liquid crystal

Abstract

The electron resonance spectrum of Coppinger's radical has been measured throughout the nematic range of p-azoxyanisole and above the nematic-isotropic transition point. Because the proton hyperfine tensors are not cylindrically symmetric about an axis perpendicular to the molecular plane it is possible to deduce not only the mole fraction of radical in the cluster but also its probable orientation within the cluster. Although the results have been interpreted within the framework of the swarm theory we could equally well have used the distortion hypothesis.